Naturalisation in Extra- Tropical Countries. 503 



Vahea Owariensis, F. v. Mueller. (Landolphia Owariensis, Beauvois.) 



Tropical West- Africa, but ascending to the highlands of Angola, 

 according to Dr. Welwitsch. This climber, with several other 

 Vaheas, yields the West-African caoutchouc ; others furnish the 

 Madagascar- sort, particularly Y. gummifera (Lamarck), now culti- 

 vated also in India. Prof. Wiesner of Vienna enumerates 47 

 species of various genera, which yield either rubber, gutta percha 

 or balata. It is said that the addition of ammonia to the sap 

 improves the rubber. V. Owariensis produces edible fruits as large 

 as middle-sized oranges, with sweet and slightly acid pulp. 



Valeriana Celtica, Linne. 



Alps of Europe ; hardy at Christiania. The " Speik." The root 

 of this perennial herb is particularly aromatic. 



Valeriana edulis, Nuttall. 



North-Western America, from Oregon to the Rocky Mountains- 

 The thick spindle-shaped root of this herb affords food to the 

 natives of that part of the globe. When baked the root proves 

 agreeable and wholesome. When we consider the wild state of the 

 plants, from which many of our important root-crops arose, this 

 Valeriana and several other plants, suggestively mentioned in these 

 pages, may well be admitted for trial-culture. 



Valeriana officinalis, Linne. 



Europe, Northern and Middle Asia, in swampy grass-land, with a 

 predilection for forests and river-banks. In Norway it extends 

 northward to lat 70 22 ' [Prof. Schuebeler]. This perennial herb 

 would do particularly well on high mountains. It is the only one 

 among numerous congeners of Europe, Asia and America, which is 

 drawn to a considerable extent into medicinal use. The root and 

 herb contain valerianic acid and a peculiar tannic acid ; the root 

 furnishes also an essential oil, which again resolves itself into 

 valerol (70 per cent.), valeren, barneol and valerianic acid. Con- 

 cerning these see Husemann and Hilger's Pflanzenstoffe, 1884. The 

 order of Valerianea? is not represented by any native plant in 

 Australia. 



Valerianella olitoria, Moench. 



Lamb's Lettuce. Europe, North- Africa, Northern and Middle 

 Asia. Northward to lat. 59 16' in Norway. A fair and early 

 salad-plant. It is an annual and has several congeners in Europe 

 and Asia. V. eriocarpa (Desvaux) is similarly utilitarian. With 

 still more force this may be said of the co-ordinal Fedia cornucopias 

 (Gaertner). The seeds will keep about five years [Vilmorin]. 



